TECHNICAL FIELD
[0001] The present invention relates to disposable diapers, and more particularly, to disposable
diapers having an opening through which the male sex organ can be drawn out.
BACKGROUND ART
[0002] Conventionally, absorbent articles for use by elderly persons, physically disabled,
etc., include, for example, disposable diapers, sweat pants, and incontinence pants
has been proposed. The absorbent articles being properly used in accordance with a
wearer's lifestyle and care level. Typically, due to their features of maintaining
and absorbing excrement without leakage, disposable diapers are used as auxiliary
tools for the care or management of excretion from people, such as the elderly and
physically disabled people, suffering from excretory problems.
[0003] However, disposable diapers may be used not only by persons suffering from difficulty
in urination on their own, but also by persons who can urinate on their own, such
as physically disabled of mild incontinence and elderly persons who can walk. However,
the physically disabled of mild incontinence and elderly persons who can walk have
inhibitions about wearing a diaper, as they have the impression that the diaper is
typically used by a person suffering from difficulty in urination by himself. This
is because the conventional diapers have no urination opening or the like for drawing
out the male sex organ from the viewpoint of preventing leakage, the opening being
provided to typical male underwear. Thus, when urinating by himself, the wearer had
to enter the cubicle, remove the diaper and urinate, for example. Such an act was
very complicated, especially, for male wearers, which gave further inhibitions in
wearing a diaper.
[0005] The absorbent article disclosed in Patent document 1 includes an inner sheet, an
outer sheet, and an intermediate sheet interposed therebetween. The absorbent article
further includes a paper-diaper main body that is divided into an abdomen part located
on the side of a wearer's abdomen, a back part located on the side of a wearer's back,
and a crotch part interposed therebetween during wearing and an absorbent core stuck
to the crotch part of the paper-diaper main body. The inner surface of the abdomen
part and the outer sheet are formed with perforations and an area for forming openings
through which the male sex organ can be drawn out during wearing. By shifting the
intermediate sheet, the openings of the inner surface of the abdomen part and the
outer sheet communicate with each other to form a through hole in the abdomen part.
With this, the absorbent article allows drawing-out/drawing-in of the male sex organ
even when wearing the diaper.
DISCLOSURE OF THE INVENTION
Problems to be Solved by the Invention
[0006] With the absorbent article disclosed in Patent document 1, however, although the
inner surface of the abdomen part and the inner sheet have openings for drawing out
the male sex organ, the openings are configured as simple openings, and are thus difficult
to enlarge in size, raising the problem of difficulty in drawing-out of the male sex
organ. Moreover, when the wearer urinates, the absorbent article required various
actions in order to draw out his male sex organ from the openings. For example, the
wearer needed to disengage a fastening member provided to the intermediate sheet so
as to shift the intermediate sheet. For wearers who can use only one hand, as a result
of paralysis, etc., for example, the need of such an action made urination on their
own difficult to carry out. Moreover, since the intermediate sheet was attached to
the fastening member, specific sound could be generated when removing the intermediate
sheet from the fastening member. With this, others could perceive wearing of the paper
diaper during urination, which increases inhibitions associated with using the paper
diaper.
[0007] The present invention is made in view of such problem, and aims to provide a disposable
diaper that allows easy drawing-out of the male sex organ during urination.
Means for Solving the Problems
[0008] In order to achieve the above-mentioned objective, the inventor has found that urination
is facilitated by providing an opening in a predetermined location of the disposable
diaper and forming a predetermined site thereof in a stretchable manner, and has reached
completion of the present invention. Specifically, the present invention provides
the disposable diaper of independent Claim 1. The dependent claims specify preferred
but optional features.
[0009] In a first aspect, there is provided a disposable diaper, including: a chassis including
at least a front body and a back body; a top sheet arranged on at least part of the
chassis, the top sheet being liquid permeable; a back sheet arranged on the top sheet
at one side in a thickness direction of the top sheet, the back sheet being liquid
impermeable; and an absorbent core arranged between the top sheet and the back sheet,
the absorbent core being liquid retainable, wherein the front body is formed with
one of an openable part or an opening, the openable part and the opening each being
formed by connecting two points positioned at a distance from each other across a
substantial center line extending in a longitudinal direction of the disposable diaper
and bisecting a width direction thereof, wherein the openable part allows the front
body to be separated at a predetermined site, and the opening allows the front body
to open at a predetermined site.
[0010] In a second aspect, the absorbent core is vertically long and is provided to at least
the front body, wherein one of the openable part and the opening each are formed in
the front body at a location away from a given outer edge of the absorbent core.
[0011] In a third aspect, the front body and the back body are joined and secured together
at a predetermined location in advance or upon wearing the disposable diaper to provide
a pants shape with a trunk opening and a pair of leg openings, in which an opening
stretch area is constituted to connect a substantially central portion of the back
body adjacent to the trunk opening and a predetermined location of the front body
adjacent to at least one of the openable part or the opening along the outer perimeter
of the pants shape, at least part of the opening stretch area being able to expand
and contract.
[0012] In a fourth aspect, the opening stretch area in a stretched state is at least 1.1
times greater than that in a non-stretched state.
[0013] In a fifth aspect, the opening stretch area includes an elastic opening area arranged
at a predetermined location on the side of the openable part or the opening in a leg
direction of the pants shape.
[0014] In a sixth aspect, the opening stretch area includes an elastic back body area arranged
in at least part of the back body adjacent to the trunk opening.
[0015] In a seventh aspect, the opening stretch area includes an elastic boundary area arranged
in at least part of a boundary between the front body and the back body, the boundary
including a joined position or an engaged position of the front body and the back
body.
[0016] In an eighth aspect, the disposable diaper further includes an auxiliary sheet provided
to the front body at a location including the openable part or the opening.
[0017] In a ninth aspect, the auxiliary sheet includes an elastic member at least in part.
[0018] In a tenth aspect, the auxiliary sheet is arranged with an absorbent core at least
in part.
[0019] The present invention can provide a disposable diaper that allows easy drawing-out
of the male sex organ during urination.
BRIEF DESCRIPTION OF THE DRAWINGS
[0020]
FIG. 1A is a front view of a disposable diaper of a first embodiment of the present
invention;
FIG. 1B is a cross-sectional view of FIG. 1A taken along the line X-X;
FIG. 2 is an exploded perspective view of the disposable diaper in the first embodiment
in the developed state;
FIG. 3A is a perspective view showing a worn state of pants-type disposable diaper;
FIG. 3B is a perspective view showing a worn state of developed-type disposable diaper;
FIG. 4A is a development view of the pants-type disposable diaper of the first embodiment;
FIG. 4B is a front view of the disposable diaper of FIG. 4A in a pants-shape;
FIG. 5A is a front view showing an opening of the disposable diaper in the first embodiment;
FIG. 5B is a front view showing another embodiment of the opening of the disposable
diaper in the first embodiment;
FIG. 5C is a front view showing yet another embodiment of the opening of the disposable
diaper in the first embodiment;
FIG. 6A is a front view showing a positional relationship between the opening and
an absorbent core;
FIG. 6B is a development view showing a positional relationship between the opening
and an absorbent core;
FIG. 7A is a perspective view showing a masking sheet as an auxiliary sheet;
FIG. 7B is a diagram showing another embodiment of the masking sheet;
FIG. 8A is a front view showing a joined position of the masking sheet;
FIG. 8B is a front view showing another joined position of the masking sheet;
FIG. 9A is a cross-sectional view showing the joined position of the masking sheet;
FIG. 9B is a cross-sectional view showing another joined position of the masking sheet;
FIG. 9C is a cross-sectional view showing another joined position of the masking sheet;
FIG. 9D is a cross-sectional view showing another joined position of the masking sheet;
FIG. 9E is a cross-sectional view showing another joined position of the masking sheet;
FIG. 10A is a front view showing a location of an elastic member;
FIG. 10B is a front view showing another location of the elastic member;
FIG. 11 is a perspective view showing a worn state of the disposable diaper in the
first embodiment;
FIG. 12 is a perspective view showing the disposable diaper in the first embodiment,
with the opening expanded;
FIG. 13A is a perspective view showing an elastic area of the disposable diaper of
the first embodiment;
FIG. 13B is a perspective view showing a state in which the opening is expanded by
extension of the elastic area thereof;
FIG. 14A is a perspective view showing an elastic area of the opening of the disposable
diaper;
FIG. 14B is a perspective view showing a state in which the opening is expanded by
extension of the elastic area thereof;
FIG. 15A is a perspective view showing an elastic back body area;
FIG. 15B is a perspective view showing a state in which the opening is expanded by
extension of the elastic back body area;
FIG. 16A is a perspective view showing an elastic boundary area;
FIG. 16B is a perspective view showing a state in which the opening is expanded by
extension of the elastic boundary area;
FIG. 17A is a developed view showing a disposable diaper in the second embodiment;
FIG. 17B is a developed view showing a positional relationship between the opening
and absorbent core of the disposable diaper in the second embodiment;
FIG. 18A is a perspective view showing a disposable diaper in the second embodiment;
FIG. 18B is a sectional view taken along the line Y-Y in FIG. 18A;
FIG. 19 is a perspective view showing a worn state of the disposable diaper in the
second embodiment;
FIG. 20 is a perspective view showing a state in which the opening of the disposable
diaper in the second embodiment is expanded;
FIG. 21 is a perspective view showing another embodiment of the masking sheet;
FIG. 22 is a perspective view showing a worn state of a disposable diaper in the third
embodiment;
FIG. 23 is a perspective view showing a state in which the opening of the disposable
diaper in the third embodiment is expanded;
FIG. 24 is a developed view showing a disposable diaper in the fourth embodiment;
FIG. 25 is a perspective view showing a worn state of the disposable diaper in the
fourth embodiment; and
FIG. 26 is a perspective view showing a state in which the opening of the disposable
diaper in the fourth embodiment is expanded.
PREFERRED MODE FOR CARRYING OUT THE INVENTION
[0021] Referring to the drawings, preferred embodiments of the present invention will be
described hereafter. It is noted that the present invention and its technical scope
are not limited thereto. For example, although an adult disposable diaper is described
in the preferred embodiments, the present invention is not limited thereto, and can
be applied to a disposable diaper for a child's toilet training, for example.
[0022] In the preferred embodiments, assuming that the side of the disposable diaper facing
a wearer's body is a skin contact side, and the side opposite the skin contact side
is a skin non-contact side.
[0023] FIG. 1A is a front view showing a disposable diaper in the first embodiment of the
present invention, and FIG. 1B is a sectional view taken along the line X-X in FIG.
1A. FIG. 2 is an exploded perspective view showing a disposable diaper in the first
embodiment in the developed state. FIG. 3A is a perspective view showing a worn state
of a pants-type disposable diaper, and FIG. 3B is a perspective view showing a worn
state of a developed-type disposable diaper. FIG. 4A is a developed view showing a
disposable diaper in the first embodiment, and FIG. 4B is a front view showing a disposable
diaper of FIG. 4A as the pants-type. FIG. 5A is a front view showing an opening of
the disposable diaper in the first embodiment, FIG. 5B is a front view showing another
form of the opening, and FIG. 5C is a front view showing another form of the opening.
FIG. 6A is a front view showing a positional relationship between the opening and
absorbent core of the disposable diaper, and FIG. 6B is a developed view showing a
positional relationship between the opening and the absorbent core. FIG. 7A is a perspective
view showing a masking sheet serving as an auxiliary sheet, and FIG. 7B is a perspective
view showing another form of the masking sheet. FIG. 8A is a front view showing a
joined position of the masking sheet, and FIG. 8B is a front view showing another
joined position of the masking sheet. FIGS. 9A to 9E are sectional views showing joined
positions of the masking sheet. FIG. 10A is a front view showing a location of an
elastic member, and FIG. 10B is a front view showing another location of the elastic
member.
[0024] FIG. 11 is a perspective view showing a worn state of the disposable diaper in the
first embodiment. FIG. 12 is a perspective view showing a state in which the opening
of FIG. 11 is expanded. FIG. 13A is a perspective view showing an elastic area of
the opening of the disposable diaper in the first embodiment, and FIG. 13B is a perspective
view showing a state in which the opening is expanded by extension of the elastic
area thereof. FIG. 14A is a perspective view showing an elastic area of the opening
of the disposable diaper, and FIG. 14B is a perspective view showing a state in which
the opening is expanded by extension of the elastic area thereof. FIG. 15A is a perspective
view showing an elastic back body area, and FIG. 15B is a perspective view showing
a state in which the opening is expanded by extension of the elastic back body area.
FIG. 16A is a perspective view showing an elastic boundary area, and FIG. 16B is a
perspective view showing a state in which the opening is expanded by extension of
the elastic boundary area. FIG. 17A is a developed view showing a disposable diaper
in the second embodiment, and FIG. 17B is a developed view showing a positional relationship
between the opening and absorbent core of the disposable diaper in the second embodiment.
FIG. 18A is a perspective view showing a disposable diaper in the second embodiment,
and FIG. 18B is a sectional view taken along the line Y-Y in FIG. 18A. FIG. 19 is
a perspective view showing a worn state of the disposable diaper in the second embodiment.
FIG. 20 is a perspective view showing a state in which the opening of the disposable
diaper in the second embodiment is expanded.
[0025] FIG. 21 is a perspective view showing another embodiment of the masking sheet. FIG.
22 is a perspective view showing a worn state of a disposable diaper in the third
embodiment. FIG. 23 is a perspective view showing a state in which the opening of
the disposable diaper in the third embodiment is expanded. FIG. 24 is a developed
view showing a disposable diaper in the fourth embodiment. FIG. 25 is a perspective
view showing a worn state of the disposable diaper in the fourth embodiment. FIG.
26 is a perspective view showing a state in which the opening of the disposable diaper
in the fourth embodiment is expanded.
1. First embodiment
1.1. General configuration
[0026] The general configuration of the disposable diaper of the present invention will
be described with regard to a disposable diaper 1 in the first embodiment. The disposable
diaper 1 includes a main body 10 and an openable part 5 formed at a predetermined
location of the main body 10. The openable part 5 is arranged to allow a wearer to
draw out his male sex organ. Therefore, the disposable diaper 1 serves essentially
as an article for males.
[0027] The openable part 5 is formed on a separation line that connects two points positioned
at a distance across a substantial center line extending in the longitudinal direction
LD or longitudinal direction of a front body 2 of the disposable diaper 1 and bisecting
the width direction WD thereof. The openable part 5 is formed by intermittently arranging
sections such as a slit or an opening on the separation line. When using the disposable
diaper 1, first, a rise direction RD-side portion of the openable part 5 is pulled
in the rise direction RD to separate portions other than the adjacent sections of
the openable part 5. With this, the openable part 5 is expanded to be ready to use.
The openable part 5 is covered with a masking sheet or auxiliary sheet 6.
1.2. Main body of the disposable diaper
[0028] Referring to FIGS. 1A to 4B, the main body 10 of the disposable diaper 1 includes
a chassis 13 that forms the outer shape of the main body 10, a liquid-permeable top
sheet 11 formed generally vertically long, a liquid-impermeable back sheet 14 formed
generally vertically long, and a liquid-retainable absorbent core 12 formed generally
vertically long. The chassis 13 is formed to provide a pants shape during wearing.
The top sheet 11 is arranged on the skin contact side of the chassis 13 and constitutes
a surface layer. The back sheet 14 is arranged on the skin non-contact side of the
chassis 13, which is one side of the top sheet 11, and constitutes a back layer. The
absorbent core 12 is arranged between the top sheet 11 and the chassis 13, i.e., between
the top sheet 11 and the back sheet 14, and constitutes an absorption layer. It is
noted that the wording "generally vertically long" includes a generally rectangular
shape having longitudinal direction LD and width direction WD. Moreover, the wording
includes a shape in which a portion of both sides in the longitudinal direction LD
is dented to the center in the longitudinal direction LD or bulged in the direction
opposite the center. Specifically, the absorbent core 12 includes an absorbent core
that is different in length in the width direction WD in a portion in the longitudinal
direction LD. Optionally, the absorbent core 12 may be arranged lengthwise either
in the width direction WD or in the rise direction RD.
[0029] The absorbent core 12 may be arranged in the state of being covered with tissues
(not shown) or a hydrophilic nonwoven fabric (not shown). When covered with a hydrophilic
nonwoven fabric, the absorbent core 12 may be configured without application of the
top sheet 11 or with only partial application thereof. This allows a reduction in
manufacturing cost, for example. The back sheet 14 may include a back sheet having
a nonwoven fabric or the like joined to the skin non-contact side. Joining a nonwoven
fabric or the like to the skin non-contact side of the back sheet 14 is desirable
in view of enhancement in wearer's feel during wearing, etc. When applying a liquid-impermeable
film to the back sheet 14, disagreeable noises due to rubbing of the liquid-impermeable
film, for example, can be prevented from occurring by joining a nonwoven fabric or
the like to the liquid-impermeable film.
[0030] The chassis 13 includes a front body 2, a back body 3, and a crotch 4 arranged therebetween
during wearing. The chassis 13 is formed to provide a pants shape by joining the front
body 2 and the back body 3 at junctions 8 or predetermined locations of the front
body 3 and the back body 3. Specifically, joining the front body 2 and the back body
3 at the junctions 8 provides a trunk opening 9 formed around a wearer's abdomen and
a pair of leg openings 7 formed around wearer's legs in the worn state. It is noted
that the predetermined location of the front body 2 and the back body 3 designates
both ends of the front body 2 and the back body 3 in the direction (refer hereafter
to as width direction WD) orthogonal to the rise direction RD in the worn state except
the leg openings 7. The front and rear bodies 2 and 3 include, for example, front
and rear bodies distinguished by the center line in the width direction WD, which
bisects the disposable diaper 1 in the developed state in the longitudinal direction
LD.
[0031] In this embodiment, a description is made about the pants-type disposable diaper
1 including trunk opening 9 and pair of leg openings 7 obtained by joining the front
body 2 and the back body 3 at the junctions 8 as shown in FIG. 3A. Without being limited
thereto, referring to FIG. 3B, the present invention can be applied to a developed-type
disposable diaper 1A that can be worn by engaging the front body 2 and the back body
3 by engaging members 8A, etc. Optionally, the present invention can be applied to
the disposable diaper 1A in which the front body 2 and the back body 3 are engaged
by reengageable engaging members, such as a hook-and-loop fastener, which are used
at the junctions 8 of the front body 2 and the back body 3 of the pants-type disposable
diaper 1. This allows easy disengagement, development, and reengagement of the disposable
diaper though the diaper is of the pants type.
[0032] The top sheet 11 is formed generally vertically long, and is arranged to extend from
the front body 2 to the back body 3 of the chassis 13 along the crotch 4. Likewise,
the absorbent core 12 is formed generally vertically long, and is arranged to extend
from the front body 2 to the back body 3 of the chassis 13 along the crotch 4. The
openable part 5 is formed in the front body 2 of the disposable-diaper main body 10
in a predetermined location of the chassis 13. For example, the openable part 5 is
formed in the front body 2 in a location at a predetermined distance away from the
absorbent core 12 so as to be generally parallel to an outer edge 41 or one end of
the absorbent core 12 in the longitudinal direction LD.
[0033] Referring to FIGS. 4A and 4B, with the disposable-diaper main body 10, a plurality
of filiform elastic members 91 are arranged at the circumference of the trunk opening
9. The elastic members 91 may be of the band type. The elastic members 91 may include
an elastic sheet that can stretch, such as a stretchable nonwoven fabric (nonwoven
fabric formed of mixed fibers of polyurethane and polypropylene or the like), a stretchable
film or the like.
[0034] A filiform elastic member or an elastic sheet that can stretch, such as a stretchable
nonwoven fabric or a stretchable film, may be provided to the front body 2 and the
back body 3 of the disposable-diaper main body 2 in their entirety or in part. Moreover,
the chassis 13 may include an elastic sheet that can stretch.
[0035] In the present invention, an anti-leakage wall or so-called leg gather assemblies
(not shown) formed using an elastic member and an anti-leakage sheet may be arranged
along both ends of the absorbent core 12 in the width direction WD. Specifically,
the anti-leakage sheet may be arranged to extend in the width direction WD of the
absorbent core 12 between the absorbent core 12 and the chassis 13 or the back sheets
14, wherein at least one elastic member is arranged at ends of the anti-leakage sheet
in the width direction WD, and is fixed with a hotmelt adhesive or the like. The anti-leakage
sheet may stay extending in the width direction WD of the absorbent core 12, or may
be folded back to the center of the absorbent core 12 in the width direction WD to
have the folded portion arranged on the skin contact side of the absorbent core 12.
[0036] With the leg gather assemblies, when extending from the absorbent core 12 in the
width direction WD thereof, the distance between the absorbent core 12 and the elastic
member of the leg gather assemblies is, preferably, in the range of more than 20 mm
in the substantial center area of the absorbent core 12 in the longitudinal direction
LD of the absorbent core 12. When the leg gather assemblies are folded back, the distance
between the absorbent core 12 and the elastic member of the leg gather assemblies
is, preferably, in the range of more than 20 mm in the state in which the anti-leakage
sheet is extended in the width direction WD in the substantial center area.
[0037] With the main body 10 of the pants-type disposable diaper 1 before wearing, the length
in the rise direction RD or maximum length in the rise direction RD from the crotch
4 to the trunk opening 9 is between 350 mm and 450 mm, for example. The maximum length
between the junctions 8 in the direction (refer hereafter to as width direction WD)
orthogonal to the rise direction RD in the developed state is between 425 mm and 900
mm, for example. It is noted that the developed state designates a state in which
the front body 2 and the back body 3 are not joined as shown in FIG. 4A. The maximum
length includes a length obtained by extending the contracted disposable-diaper main
body 10 in the width direction WD and the rise direction RD or the leg direction LGD
by an elastic force of filiform elastic members or substrate sheets as will be described
later.
[0038] With the disposable diaper 1 for children, the length of the main body 10 of the
pants-type disposable-diaper 1 in the rise direction RD before wearing is between
200 mm and 300 mm, for example. The maximum length between the junctions 8 in the
width direction WD of the disposable-diaper main body 10 in the developed state is
between 300 mm and 450 mm, for example.
[0039] In this embodiment, the back sheet 14 is arranged on the wearer's skin non-contact
side. Without being limited thereto, the back sheet 14 may be arranged between the
absorbent core 12 and the chassis 13 or between sheets when the chassis 13 includes
a plurality of sheets.
1.3. Openable part
[0040] Referring to FIG. 5A, the openable part 5 is obtained by, for example, intermittently
(at intervals b) forming sections, such as slits or openings (like perforations, for
example). By breaking the portions interposed between the adjacent sections, the openable
part 5 can provide an opening of a predetermined size. The maximum length of the openable
part 5 in the developed state is more than 100 mm and in the range of less than 60%
of the maximum length of the disposable-diaper main body 10 in the width direction
WD in the developed state, for example. Preferably, the maximum length is more than
120 mm and in the range of less than 40% of the length of the disposable-diaper main
body 10 in the width direction WD. This is because the openable part 5 requires a
length of more than 100 mm to allow the wearer to draw out his male sex organ. When
the length of the openable part 5 exceeds the range of 60% of the length of the disposable-diaper
main body 10 in the width direction WD, the disposable diaper 1 is difficult to pull
up during wearing, leading to poor ease of use.
[0041] Specifically, when the length of the disposable diaper 1 in the width direction WD
is 550 mm, the length of the openable part 5 is 200 mm.
[0042] With the pitch of the sections a as formed intermittently, the sections a in the
range from 1.0 mm to 20.0 mm can be continuously formed at intervals b in the range
from 0.5 mm to 5.0 mm, for example. Preferably, the range of the sections a is from
2.0 mm to 8.0 mm, and the range of interval b is from 1.0 mm to 3.0 mm. Preferably,
the length of the sections a is equal to or greater than the length of the intervals
b.
[0043] A cleavage (not shown) of 25 mm to 60 mm may be arranged substantially in the center
of the openable part 5. It is noted that the cleavage designates a cut formed in a
portion of the chassis 13 corresponding to the openable part 5. Thus, arranging the
cleavage substantially in the center of the openable part 5 allows the wearer to insert
his fingers, etc. into the cleavage so as to easily expand therefrom the openable
part 5, for example. When stiffening members as will be described later are arranged
at both ends of the openable part 5, the cleavage is arranged, preferably, in advance
in a portion of each stiffening member located in the openable part 5. This is because
even if a plurality of sections are to be intermittently formed in a continuous manner
and are arranged in the portion of the stiffening member located in the openable part
5, portions between the sections a will become difficult to separate due to presence
of the stiffening member.
[0044] Specifically, the length of the cleavage is 40 mm. The length of the cleavage arranged
in the stiffening member area in the openable part 5 is 30 mm. With the openable part
5 having a 200 mm length, for example, the length of the cleavage arranged in the
stiffening member at each end of the openable part 5 is 30 mm, the length of the cleavage
arranged substantially in the center of the openable part 5 is 40 mm, the length of
the sections a located between the cleavage at each end of the openable part 5 and
the cleavage substantially in the center thereof is 4.0 mm, and the length of the
interval b is 1.0 mm.
[0045] In this embodiment, the openable part 5 is obtained by intermittently forming the
sections, such as slits or openings, in a continuous manner. Without being limited
thereto, referring to FIG. 5B, the openable part 5 may be formed by arranging a separation-line
part wherein the thickness and thus strength of the corresponding portion of the chassis
13 is reduced with respect to other portions thereof. In this embodiment, the openable
part 5 is formed like a straight line. Without being limited thereto, the openable
part may be formed like a curve and a combination of a straight line and a curve,
for example. Optionally, referring to FIG. 5C, by cutting a portion of the absorbent
core 12, the openable part 5 may be formed with a curve or straight line with respect
to the cut. Optionally, by arranging in a portion of the absorbent core 12 an area
for openable part 5, the openable part 5 may be arranged inside the absorbent core
12.
[0046] When the openable part 5 is obtained by intermittently forming the sections a such
as slits or openings or arranging the separation-line part, the stiffening members
(not shown) are joined, preferably, to both ends of the openable part 5 of the chassis
13 so as not to break both ends of the openable part 5. When the chassis 13 includes
a plurality of components, the stiffening members may be interposed between the components
and at the sites corresponding to both ends of the openable part 5.
[0047] The stiffening members may be formed of a nonwoven fabric, a film or the like having
more than 5N tear strength (measuring method: A-1 (single tongue method), JIS L 1906)
both in the width direction WD and in the longitudinal direction LD, for example.
The size of the stiffening members is 60 mm long (rise direction RD) and 40 mm wide
(width direction WD), for example. The stiffening members may be joined to both ends
of the openable part 5 using hotmelt adhesion, heat-sealing, ultrasonic sealing, etc.,
for example. When the chassis 13 constituting the front body 2 includes a plurality
of components, the stiffening members may be arranged between the components, which
are then joined or fixed from both surfaces.
[0048] The openable part 5 may be formed, at both ends thereof, with a shape of a smooth
curve such as a circle or an ellipse, for example. Specifically, holes having shapes
of a smooth curve such as a circle or an ellipse may be arranged at both ends of the
openable part 5. Thus, arranging holes of a predetermined shape at both ends of the
openable part 5 allows increasing the anti-tear strength of the openable part 5 at
both ends when expanding the openable part 5. Moreover, with the openable part 5 having
other configuration than the configuration of intermittently forming the sections
such as slits or openings or the configuration of forming the separation-line part,
arranging holes of a predetermined shape at both ends of the openable part 5 allows
dispersion of forces applied to both ends of the openable part 5 when expanding the
openable part 5, leading to prevention of breakage of both ends of the openable part
5.
[0049] Moreover, cut lines may be arranged at both end of the openable part 5 to extend
in the direction different from the direction of the slit or the like or the separation-line
part of the openable part 5. The cut lines arranged at both ends may be any of an
arc, a curve, or a straight line. Thus, arranging the cut lines at both ends of the
openable part 5 to extend in predetermined directions allows increasing the anti-tear
strength of the openable part 5 at both ends when expanding the openable part 5.
[0050] In this embodiment, the openable part 5 is configured to be like a straight line
by the sections such as slits or openings that are formed intermittently in a continuous
manner. Without being limited thereto, the openable part 5 may be configured like
a curve, a straight line or a combination thereof, for example, wherein the curve
or the straight line connects two points positioned at a distance across the substantial
center line extending in the longitudinal direction LD of the front body 2 of the
disposable diaper 1 and bisecting the width direction WD thereof. Specifically, the
openable part 5 may be formed like a waveshape, a mountain shape, etc. Moreover, the
openable part 5 may be configured so that part or all of the openable part 5 can be
cut off. For example, the openable part 5 may be formed in the shape of a circle,
an ellipse, a polygon or the like, wherein part or all of the portion can be cut off.
[0051] For the purpose of easy recognition of the location of the openable part 5, the openable
part 5 may be colored in the rise direction RD side or leg-direction side of the openable
part 5 or provide the irregularities by embossing, etc., for example. Thus, the openable
part 5 may be configured to provide a sign for facilitating recognition of the location
of the openable part 5 visually or tactually. Providing such visual or tactual signs
allows easy recognition of the location of the openable part 5 when the wearer urinates
by himself, for example, leading to easier urination. Moreover, when assisting urination
of a bedridden patient, etc., for example, a caregiver can easily recognize the location
of the openable part 5 of the disposable diaper 1 worn by the patient, etc., leading
to the facilitation of providing assistance to in care patients.
[0052] An opening auxiliary such as a handle may be provided to the openable part 5. Providing
the opening auxiliary allows the wearer to easily separate the openable part 5 using
the opening auxiliary, for example. Moreover, this allows easy enlargement of the
openable part 5 when assisting in care bedridden patients urinate, for example.
1.4. Location of the openable part
[0053] Referring to FIG. 6A, the openable part 5 is located in the range of a trunk periphery
23 of the front body 2. Preferably, the openable part 5 is arranged at a location
of the front body 2 at a predetermined distance away from one side or a given outer
edge 41 of the generally vertically long absorbent core 12, which extends in the width
direction WD. It is noted that "location a predetermined distance away" includes a
location away in the rise direction RD and a location away in the leg direction LGD,
for example. Therefore, the openable part 5 may be arranged in part of the absorbent
core 12 on condition that the openable part 5 is located in the range of the trunk
periphery 23. In this case, the absorbent core 12 is formed, preferably, with its
periphery around the openable part 5 being sealed so as not to leak a material of
the absorbent core 12.
[0054] With the location of the openable part 5, referring to FIG. 6B, assuming that the
distance from the end of the trunk opening 9 to the lower end of the openable part
5 is c, the distance from the lower end of the openable part 5 to a longitudinal direction
center L in the developed state is d, and the distance from the end of the trunk opening
9 to the longitudinal direction center L in the developed state is e, a value of d/c
is, preferably, in the range from 0.65 to 8.0, for example.
[0055] Specifically, the distance c from the end of the trunk opening 9 to the lower end
of the openable part 5 is, preferably, in the range from 50 mm to 270 mm. The distance
d from the lower end of the openable part 5 to the longitudinal direction center L
in the developed state is, preferably, in the range from 180 mm to 400 mm. The distance
e from the end of the trunk opening 9 to the longitudinal direction center L in the
developed state is, preferably, in the range from 350 mm to 450 mm.
[0056] Moreover, the openable part 5 is arranged, preferably, on the rise direction RD side
of the absorbent core 12. Specifically, assuming that the distance from the longitudinal
direction end of the absorbent core 12 in the front body 2 to the longitudinal direction
center L in the developed state is f, and the distance from the lower end of the openable
part 5 to the longitudinal direction end of the absorbent core 12 in the front body
2 is g, a value of d/f is, preferably, in the range from 1.0 to 2.3. Specifically,
the distance f from the longitudinal direction end of the absorbent core 12 in the
front body 2 to the longitudinal direction center L in the developed state is, preferably,
in the range from 175 mm to 395 mm. The distance g from the lower end of the openable
part 5 to the longitudinal direction end of the absorbent core 12 in the front body
2 is, preferably, in the range from 5 mm to 225 mm.
[0057] With a disposable diaper smaller than the disposable diaper 1 in this embodiment,
i.e., disposable diaper for children so called, the distance c from the end of the
trunk opening 9 to the lower end of the openable part 5 is, preferably, in the range
from 35 mm to 180 mm, for example. The distance d from the lower end of the openable
part 5 to the longitudinal direction center L in the developed state is, preferably,
in the range from 120 mm to 265 mm. The distance e from the end of the trunk opening
9 to the longitudinal direction center L in the developed state is, preferably, in
the range from 200 mm to 300 mm.
[0058] With the absorbent core 12 for children, the distance f from the longitudinal direction
end of the absorbent core 12 in the front body 2 to the longitudinal direction center
L in the developed state is, preferably, in the range from 115 mm to 260 mm. The distance
g from the lower end of the openable part 5 to the longitudinal direction end of the
absorbent core 12 in the front body 2 is, preferably, in the range from 5 mm to 150
mm.
1.5. Masking sheet
[0059] Referring to FIG. 7A, the masking sheet 6 is formed generally rectangularly. The
masking sheet 6 is joined to the skin contact side or skin non-contact side of the
chassis 13 in such a manner as to cover the openable part 5. The length of the masking
sheet 6 in the longitudinal direction LD is greater than the length of the openable
part 5 in the width direction WD. Specifically, the masking sheet 6 only needs to
have a length that allows covering of the openable part 5 in the entire width direction
WD.
[0060] The masking sheet 6 is formed by holding a plurality of filiform elastic members
63 in the extended state by a pair of band-like substrate sheets 61 and 62, bonding
the substrate sheets 61 and 62 together, and releasing the tension of the elastic
members 63. With this, the masking sheet 6 provides a plurality of slacks or so-called
gathers. The masking sheet 6 can be extended by an extendable part of the gathers.
In other words, the gathers will disappear by extending the masking sheet 6. Thus,
the masking sheet 6 can make contact with a wearer's abdomen by an elastic force of
the elastic members 63 during wearing, and can follow the expanded state of the openable
part 5 and extend by a part of the gathers when the wearer expands the openable part
5, for example.
[0061] Referring to FIG. 7B, the masking sheet 6 may be formed by bonding a band-like elastic
member 64 and the substrate sheet 61 together. Alternatively, the masking sheet 6
may be formed by holding the band-like elastic member 64 by the pair of substrate
sheets 61 and 62 and bonding the substrate sheets 61 and 62 together. Optionally,
the masking sheet 6 may be formed by folding the substrate sheet 61 and holding the
elastic members 63 and 64 therebetween. The band-like elastic member may be a substrate
sheet such as an elastic nonwoven fabric, which can be used as the masking sheet 6.
[0062] The masking sheet 6 is joined to the chassis 13 at a junction 65 in such a manner
as to cover all the openable part 5 formed in the front body 2. With the junction
65 of the masking sheet 6 and chassis 13, referring to FIG. 8A, the masking sheet
6 may be joined to the chassis 13 at a portion of the openable part 5 in the leg direction
LGD or at both ends of the masking sheet 6 in the longitudinal direction LD, for example.
Alternatively, referring to FIG. 8B, the masking sheet 6 may be joined to the chassis
13 at a portion of the openable part 5 in the rise direction RD or at both ends of
the masking sheet 6 in the longitudinal direction LD. The junction 65 may be a continuous
or discontinuous junction made with respect to the chassis 13.
[0063] Referring to FIGS. 9A to 9D, the masking sheet 6 may be joined to the skin contact
side of the chassis 13 via the rise direction RD of the openable part 5 as shown in
FIG. 9A, or to the skin non-contact side of the chassis 13 via the rise direction
RD of the openable part 5 as shown in FIG. 9B. Optionally, the masking sheet 6 may
be joined to the skin contact side of the chassis 13 via the leg direction LGD of
the openable part 5 as shown in FIG. 9C, or to the skin non-contact side of the chassis
13 via the leg direction LGD of the openable part 5 as shown in FIG. 9D. Referring
to FIG. 9E, when the masking sheet 6 is joined to the skin contact side of the chassis
13 in the leg direction LGD of the openable part 5, the masking sheet 6 may be formed
in such a manner as to cover the junction 65 with the top sheet 11.
[0064] Thus, the masking sheet 6 includes elastic members 63 in its entirety or in part.
For example, when the masking sheet 6 is arranged on the skin non-contact side of
the openable part 5, the masking sheet 6 allows the chassis 13 in the openable part
5 to make contact with a wearer's skin, etc. and to prevent the wearer's skin, etc.
from being exposed. When the masking sheet 6 is arranged on the skin contact side
of the openable part 5, the masking sheet 6 allows the chassis 13 in the openable
part 5 to be drawn to the wearer's skin and to prevent the wearer's skin, etc. from
being exposed.
[0065] The masking sheet 6 may be arranged with an absorbent core in its entirety or in
part. With this, during urination, even if urine is discharged before drawing out
the male sex organ, for example, discharged urine can be absorbed by the masking sheet
6.
1.6. Elastic member adjacent to the openable part
[0066] Referring to FIG. 10A, when the masking sheet 6 is joined to the skin contact side
of the chassis 13 via the rise direction RD of the openable part 5 (refer to FIG.
9 A), an elastic member is arranged, preferably, in at least part of a crotch area
51 adjacent to the openable part 5. The elastic member may be either filiform or like
a sheet.
[0067] Referring to FIG. 10B, when the masking sheet 6 is joined to the skin contact side
of the chassis 13 in the leg direction LGD of the openable part 5 (refer to FIG. 9C),
the elastic member is arranged, preferably, in at least part of a rise area 52 adjacent
to the openable part 5. The elastic member may be either filiform or like a sheet.
[0068] Thus, by joining to the chassis 13 the masking sheet 6 having an elastic member arranged,
the openable part 5 can be opened and closed as required without exposing a wearer's
skin.
1.7. Usage mode
[0069] A description will be made about the usage mode of the disposable diaper 1 in the
first embodiment of the present invention.
[0070] Referring to FIG. 11, in this embodiment, the disposable diaper 1 is of the pants
type, which can be worn and used like typical pants by a wearer. During urination,
the wearer pulls part of a rise direction RD part of the front body 2 adjacent to
the openable part 5 having sections such as slits and openings formed intermittently,
or part of the front body 2 at the trunk opening 9, cleaving and expanding the openable
part 5. Subsequently, referring to FIG. 12, the wearer holds or catches a substantial
center of the opening of the openable part 5 with his fingers, etc., and pulls it
in the leg direction LGD. With this, the opening of the openable part 5 is extended
in the leg direction LGD to allow securing of the opening of a predetermined size.
Specifically, referring to FIGS. 13A and 13B, when the wearer holds or catches a substantial
center of the opening of openable part 5 with his fingers, etc., and pulls it in the
leg direction LGD, at least part of an opening stretch area 53 (refer to FIG. 13A)
is extended by an elastic force, the area 53 being an area connecting a substantially
central portion of the back body 3 adjacent to the trunk opening 9 and a substantially
central portion of the front body 2 adjacent to the openable part 5 along the outer
perimeter of the pants shape. Then, the opening of the openable part 5 is extended
in the leg direction LGD to allow securing of the opening of a predetermined size
(refer to FIG. 13B).
[0071] With a stretch part, referring to FIGS. 14A and 14B, using a stretchable elastic
member, an elastic opening area 54 may be arranged on the leg-direction side of the
openable part 5 in the open direction to serve as the opening stretch area 53, for
example. Alternatively, referring to FIGS. 15A and 15B, using a stretchable elastic
member, an elastic back body area 55 may be arranged on the perimeter of the back
body 3 adjacent to the trunk opening 9 to serve as the opening stretch area 53, for
example. Optionally, referring to FIGS. 16A and 16B, using a stretchable elastic member,
an elastic boundary area 56 may be arranged in all or part of a boundary area including
a joined or engaged position between the front body 2 and the back body 3 to serve
as the opening stretch area 53, for example. Optionally, a combination of the elastic
opening area 54, elastic back body area 55, and elastic boundary area 56 may be arranged
to serve as the opening stretch area 53.
[0072] When the openable part 5 does not provide an opening before use due to the formation
of the sections, such as slits and openings that are formed intermittently in a continuous
manner, etc., the openable part 5 should be opened in advance by pulling part of the
front body 2 in the leg direction LGD or in the rise direction RD.
[0073] Thus, the wearer can secure the opening of a predetermined size with a single hand,
leading to the easy drawing-out of his male sex organ. With this, the wearer can easily
urinate without removing the diaper 1. Moreover, the openable part 5 has the open
direction conforming to the leg direction LGD, and the opening shape extending in
the width direction WD of the disposable diaper 1, leading to the easy expansion of
the openable part 5 by either a right-handed wearer or a left-handed wearer. Moreover,
since the masking sheet 6, which can be stretched, is joined to the skin contact side
of the openable part 5, the chassis 13 can make contact with a wearer's abdomen during
ordinary wearing and after urination, leading to prevention of the skin from being
unnecessarily exposed.
2. Other embodiments
[0074] Referring to FIGS. 17A to 26, the second to fourth embodiments of the present invention
will be described. The second embodiment depicts an implementation in which an opening
5B is formed by superimposing chassis 13A and 13B one upon another at a predetermined
location of the front body 2. The third embodiment depicts an implementation in which
an elastic member is arranged at the boundary between the front body 2 and the back
body 3 to reduce stress acting on parts of an openable part 5C in the rise direction
RD and in the leg direction LGD as compared with stress acting on other parts. The
fourth embodiment depicts an implementation in which an opening 5D is formed by superimposing
chassis 13C and 13D one upon another at a predetermined location of the front body
2, wherein an elastic member is arranged at the boundary between the front body 2
and the back body 3 to reduce stress acting on parts of the opening 5D in the rise
direction RD and in the leg direction LGD as compared with stress acting on other
parts.
[0075] In the following embodiments, omission of the description means that the description
has been made in connection with the first embodiment, and like references designate
like parts in the first embodiment.
2.1. Second embodiment
[0076] Referring to FIGS. 17A to 20, a disposable diaper 1B in the second embodiment of
the present invention will be described. As seen from FIGS. 17A to 20, the disposable
diaper 1B in the second embodiment differs from the disposable diaper 1 in the first
embodiment in the configuration of forming the opening 5B. Specifically, referring
to FIGS. 17A and 17B, a rectangular chassis 13B is superimposed upon a chassis 13A
by a predetermined amount at a predetermined location of the front body 2 to provide
a superimposed portion, and the chassis 13B and 13A are joined together at a pair
of junctions 21 or both sides of the superimposed portion, forming the front body
2. The superimposed portion comes into a state where it is able to be opened, by arranging
a non-joined part 22 substantially in the center of the front body 2. Thus, in the
second embodiment, the opening 5B is formed in the disposable diaper 1B.
[0077] The maximum length of the opening 5B in the developed state is more than 100 mm and
in the range of less than 60% of the maximum length of the disposable-diaper main
body 10 in the width direction WD in the developed state, for example. Preferably,
the maximum length of the opening 5B is more than 120 mm and in the range of less
than 40% of the maximum length of the disposable-diaper main body 10 in the width
direction WD. This is because the opening 5B requires a length of more than 100 mm
to allow the wearer to draw out his male sex organ. When the length of the opening
5B exceeds the range of 60% of the length of the disposable-diaper main body 10 in
the width direction WD, the disposable diaper 1B becomes difficult to pull up during
wearing, leading to poor ease of use.
[0078] The length of the superimposed portion in the front body 2 is more than 15 mm, for
example. Preferably, the length of the superimposed portion is more than 30 mm. The
non-joined part 22 includes filiform elastic members 63 in its entirety or in part.
The elastic members 63 may be band-like elastic members such as a stretchable nonwoven
fabric or a stretchable film.
[0079] The openable non-joined part 22 may have a predetermined shape such as a dot shape,
a portion of which can be joined in the easily removable state. Specifically, the
non-joined part 22 may not be joined in its entirety or may be joined in part by a
joining means or device that can be removed easily. The joining method of the junctions
21 includes hotmelt adhesion, heat-sealing, ultrasonic sealing, etc.
[0080] For the purpose of easy recognition of the location of the opening 5B, the opening
5B may be colored on the rise direction RD side or leg-direction side of the opening
5B or provide the irregularities by embossing, etc., for example. Thus, the opening
5B may be configured to provide a sign for facilitating recognition of the location
of the opening 5B visually or tactually. It is desirable that providing such visual
or tactual sign allows easy recognition of the location of the opening 5B when the
wearer urinates by himself, for example, leading to easier urination. Moreover, when
assisting urination of a bedridden patient, etc., for example, a caregiver can easily
recognize the location of the opening 5B of the disposable diaper 1B worn by the patient,
etc., leading to facilitation of urination assistance in care.
[0081] An opening auxiliary such as a handle may be provided to the opening 5B. It is desirable
that providing the opening auxiliary allows the wearer to easily separate the opening
5B using the opening auxiliary, for example. Moreover, this allows easy enlargement
of the opening 5 when assisting urination of a bedridden patient, etc. in care, for
example.
[0082] Preferably, the opening 5B is located in the range of the trunk periphery 23 of the
front body 2. Specifically, the opening 5B is arranged at a location of the front
body 2 a predetermined distance away from a given outer edge of the absorbent core
12, i.e., one side of the absorbent core 12 extending in the width direction WD. With
the location of the opening 5B, assuming that the distance from the end of the trunk
opening 9 to the upper end of the chassis 13A is h, the distance from the upper end
of the chassis 13A to the longitudinal direction center L in the developed state is
i, and the distance from the end of the trunk opening 9 to the longitudinal direction
center L in the developed state is j, a value of i/h is, preferably, in the range
from 0.65 to 8.0.
[0083] Specifically, the distance h from the end of the trunk opening 9 to the upper end
of the chassis 13A is, preferably, in the range from 50 mm to 270 mm. The distance
i from the upper end of the chassis 13A to the longitudinal direction center L in
the developed state is, preferably, in the range from 180 mm to 400 mm. The distance
j from the end of the trunk opening 9 to the longitudinal direction center L in the
developed state is, preferably in the range from 350 mm to 450 mm.
[0084] Preferably, the opening 5B is arranged on the rise direction RD side of the absorbent
core 12. Specifically, assuming that the distance from the longitudinal direction
end of the absorbent core 12 in the front body 2 to the longitudinal direction center
L in the developed state is k, and the distance from the upper end of the chassis
13A to the longitudinal direction end of the absorbent core 12 in the front body 2
is 1, a value l/k is, preferably, in the range from greater than 1.0 to less than
2.3. Specifically, the distance k from the longitudinal direction end of the absorbent
core 12 in the front body 2 to the longitudinal direction center L in the developed
state is, preferably, in the range from 175 mm to 395 mm. The distance l from the
upper end of the chassis 13A to the longitudinal direction end of the absorbent core
12 in the front body 2 is, preferably, in the range from 5 mm to 225 mm.
[0085] With the disposable diaper that is smaller than the disposable diaper 1B in this
embodiment, i.e., so called disposable diapers for children, the distance h from the
end of the trunk opening 9 to the upper end of the chassis 13A is, preferably, in
the range from 35 mm to 180 mm, for example. The distance i from the upper end of
the chassis 13A to the longitudinal direction center L in the developed state is,
preferably, in the range from 120 mm to 265 mm. The distance j from the end of the
trunk opening 9 to the longitudinal direction center L in the developed state is,
preferably, in the range from 200 mm to 300 mm.
[0086] With the absorbent core 12 for children, the distance k from the longitudinal direction
end of the absorbent core 12 in the front body 2 to the longitudinal direction center
L in the developed state is, preferably, in the range from 115 mm to 260 mm. The distance
1 from the upper end of the chassis 13A to the longitudinal direction end of the absorbent
core 12 in the front body 2 is, preferably, in the range from 5 mm to 150 mm.
[0087] Referring to FIGS. 18A and 18B, an elastic member is provided, preferably, to at
least one of the chassis 13A and 13B adjacent to the opening 5B. In this case, the
elastic member may be either filiform or like a sheet. The elastic member may be provided
to both of the chassis 13A and 13B adjacent to the opening 5B.
[0088] Referring to FIGS. 19 and 20, with the usage mode of the disposable diaper 1B, the
wearer catches a substantial center of the chassis 13A of the opening 5B formed in
the non-joined part 22 with his fingers, and pulls it in the leg direction LGD. With
this, the elastic back body area 55 or part of the opening stretchable area 53 is
extended by an elastic force, so that the opening 5B is extended in the leg direction
LGD, facilitating securing of the opening of a predetermined size.
[0089] Thus, in the front body 2, by superimposing the chassis 13A and 13B one upon another
to provide the opening 5B defined by the junctions 21 and the non-joined part 22 and
arranging the elastic members 63 at the opening 5B, the opening 5 can be formed, which
can be opened as required. When the non-joined part 22 is joined in the dot shape
as well, joining can easily be removed, allowing forming of the opening 5B that can
be opened as required. No masking sheet 6 is arranged in the second embodiment. Without
being limited thereto, the masking sheet 6 may be arranged in the second embodiment
as in the first embodiment.
2.2. Third embodiment
[0090] Referring to FIGS. 21 to 23, a disposable diaper 1C in the third embodiment of the
present invention will be described. Referring to FIG. 22, the disposable diaper 1C
includes a filiform elastic member or a band-like elastic member such as a stretchable
nonwoven fabric or a stretchable film arranged adjacent to the boundary including
a joined or engaged position between the front body 2 and the back body 3 to serve
as the elastic boundary area 56. With this, on the trunk periphery 23, stress acting
on parts of the openable part 5C in the rise direction RD and in the leg direction
LGD is reduced as compared with stress acting on other parts. Adjacent to the leg
openings 7, the --------------------→ filiform elastic member or the band-like elastic
member such as a stretchable nonwoven fabric or a stretchable film may be arranged
around the circumference in its entirety or in part, or may not arranged therearound.
[0091] Referring to FIG. 21, in the third embodiment, the disposable diaper 1C can use a
masking sheet 6C having a single nonwoven fabric 67 of 10 g/m
2 to 30 g/m
2 or a lamination of nonwoven fabrics 67. In this case, the masking sheet 6C does not
necessarily require an elastic member. When the masking sheet 6C is composed of a
plurality of nonwoven fabrics 67, a liquid-impermeable sheet 66 such as a polyethylene
(PE) or polypropylene (PP) film may be placed on any one of the nonwoven fabrics 67.
[0092] Thus, in the third embodiment, the disposable diaper 1C can maintain the length of
the openable part 5C in the worn state close to the maximum length by reducing stress
acting on the parts of the openable part 5C in the rise direction RD and in the leg
direction LGD as compared with stress acting on other parts. The elastic boundary
area 56 or part of the opening stretchable area 53 is extended by an elastic force,
so that the openable part 5C is extended in the leg direction LGD, facilitating securing
of the opening of a predetermined size.
2.3. Fourth embodiment
[0093] Referring to FIGS. 24 to 26, a disposable diaper 1D in the fourth embodiment of the
present invention will be described. Referring to FIG. 24, the disposable diaper 1D
in the fourth embodiment differs from the disposable diaper 1 in the first embodiment
in the configuration of forming the opening 5D. Specifically, a rectangular chassis
13D is superimposed upon a chassis 13C by a predetermined amount at a predetermined
location of the front body 2 to provide a superimposed portion, and the chassis 13D
and 13C are joined together at a pair of junctions 21 or both sides of the superimposed
portion, forming the front body 2. The superimposed portion becomes openable by arranging
a non-joined part 22 substantially in the center of the front body 2.
[0094] The non-joined part 22 may have a predetermined shape such as a dot shape, a portion
of which can be joined in the easily removable state. Specifically, the non-joined
part 22 may not be joined in its entirety or may include a weakly joined portion that
can be removed easily. The joining method of the junctions 21 includes hotmelt adhesion,
heat-sealing, ultrasonic sealing, etc.
[0095] The length of the superimposed portion in the front body 2 is greater than 15 mm,
for example. Preferably, the length of the superimposed portion is greater than 30
mm.
[0096] Referring to FIGS. 25 and 26, in the fourth embodiment, the disposable diaper 1D
includes a filiform elastic member or a band-like elastic member such as a stretchable
nonwoven fabric or a stretchable film arranged adjacent to the boundary including
a joined or engaged position between the front body 2 and the back body 3 to serve
as the elastic boundary area 56. With this, on the trunk periphery 23, stress acting
on parts of the openable part 5C in the rise direction RD and in the leg direction
LGD is reduced as compared with stress acting on other parts. Adjacent to the leg
openings 7, the filiform elastic member or the band-like elastic member such as a
stretchable nonwoven fabric or a stretchable film may be arranged around the circumference
in its entirety or in part, or it may not be arranged therearound.
[0097] Thus, with the disposable diaper 1D in the fourth embodiment, the chassis 13C and
13D are superimposed one upon another in the front body 2 to arrange the opening 5D
defined by the junctions 21 and the non joint 22. The disposable diaper 1D can maintain
the length of the opening 5D in the worn state close to the maximum length by reducing
stress acting on the parts of the opening 5D in the rise direction RD and in the leg
direction LGD as compared with stress acting on other parts. Moreover, the elastic
boundary area 56 or part of the opening stretchable area 53 is extended by an elastic
force, so that the opening 5D is extended in the leg direction LGD, facilitating securing
of the opening of a predetermined size. Additionally, when the non-joined part 22
is weakly joined to the dot shape area, joining can easily be removed allowing the
forming of the opening 5D that can be opened as required.
[0098] The trunk periphery 23 may be formed with a substrate sheet, which can be stretched,
in place of an elastic member.
3. Components
[0099] The components of the disposable diaper 1 will be described hereafter.
3.1. Main body of the disposable diaper
3.1.1. Top sheet
[0100] The top sheet 11 is arranged on the wearer's body side during use to make contact
with excrement. The top sheet 11 may be liquid permeable over the entire surface or
part thereof. The top sheet 11 may be composed of either a single sheet-like member
or a plurality of sheet-like members bonded together.
[0101] Preferably, the top sheet 11 is made of a material having a strength that can resist
damage even when undergoing a load due to compression, twist, friction, etc. during
wearing and providing no stimulus to the skin, for example. A sheet-like material
having liquid permeability can be adopted such as a fabric, a nonwoven fabric or a
perforated plastic sheet, for example. An example of the nonwoven fabric is a fabric
made of hydrophobic fibers of polyolefin or polyester subjected to hydrophilic treatment
and manufactured by pointbond, airthrough, spunbond or the like. Examples of materials
of the nonwoven fabric are natural and chemical fibers having a basis weight of 15
g/m
2 to 35 g/m
2. An example of natural fibers is cellulose such as cotton. Examples of chemical fibers
are semi-synthetic cellulose such as rayon, regenerated cellulose, acetate or triacetate,
thermoplastic hydrophobic chemical fiber, and thermoplastic hydrophobic chemical fiber
subjected to hydrophilic treatment. Examples of thermoplastic hydrophobic chemical
fibers are single fiber made of polyethylene (PE), polypropylene (PP) or polyethylene
terephthalate (PET), fiber obtained by graft polymerization of polyethylene (PE) and
polypropylene (PP), and composite fiber having core/sheath structure or the like.
[0102] Examples of the perforated plastic sheet are perforated sheets of thermoplastic resin
such as polyethylene (PE), polypropylene (PP) or polyethylene terephthalate (PET)
and a perforated sheet of a porous foaming material.
3.1.2. Absorbent core
[0103] The absorbent core 12 serves to absorb and hold discharged bodily fluids such as
urine. Examples of the absorbent core are a mixed laminate of high absorbent polymer
and hydrophilic fibers and a structure having high absorbent polymer fixed to hydrophilic
sheets with a hotmelt adhesive, etc. An example of the high absorbent polymer is an
absorbent polymer such as polyacrylate or starch acrylate, wherein the components
having a water absorption capacity of 20 g/g or more and a particle size of 100 µm
to 800 µm constitute 80% or more. Examples of the hydrophilic fibers are crushed pulp
fibers and rayon fibers. Examples of the hydrophilic sheets are sheets made of nonwoven
fabrics having a basis weight of 15 g/m
2 to 35 g/m
2 and obtained from hydrophobic fibers of polyolefin, polyester, etc. subjected to
hydrophilic treatment, the sheets being manufactured by pointbond, airthrough, spunbond
or the like. An example of the hotmelt adhesive is an adhesive containing as a base
polymer a styrene-butadiene-styrene copolymer (SBS), a styrene-isobutylene-styrene
copolymer (SIS), a styrene- ethylene-butylene-styrene copolymer (SEBS), a styrene-ethylene-propylene-styrene
copolymer (SEPS), an amorphous poly-alpha-olefin (APAO) or the like.
3.1.3. Chassis
[0104] The chassis 13 provides an outer shape of the main body 10 of the disposable diaper
1. The chassis 13 may be composed of either a single sheet-like member or a plurality
of sheet-like members bonded together. In the first embodiment, the disposable diaper
1 is configured so that the chassis 13 includes a front body 2, a back body 3, and
a crotch 4, wherein the top sheet 11, absorbent core 12, and back sheet 14 are arranged
at predetermined locations of the chassis 13. Without being limited thereto, the chassis
13 may include the front body 2 and the back body 3, wherein the crotch 4 having the
top sheet 11, absorbent core 12, and back sheet 14 may independently be joined to
the chassis 13. In this alternative, the back sheet 14 and the chassis 13 may be joined
at the crotch 4, and the back sheet 14 may be configured to play a role of the chassis
13.
[0105] Preferably, the chassis 13 is made of a material having a strength that can resist
damage even when undergoing a load due to compression, twist, friction, etc. during
wearing and providing no stimulus to the skin, for example. A sheet-like material
having gas permeability can be adopted such as a nonwoven fabric or a perforated plastic
sheet, for example. An example of the nonwoven fabric is a fabric made of synthetic
fibers of polyolefin or polyester and manufactured by pointbond, airthrough, spunbond
or the like. Examples of materials of the nonwoven fabric are natural and chemical
fibers having basis weight of 15 g/m
2 to 35 g/m
2. An example of natural fibers is cellulose such as cotton. Examples of chemical fibers
are semi-synthetic cellulose such as rayon, regenerated cellulose, acetate or triacetate,
thermoplastic hydrophobic chemical fiber, and thermoplastic hydrophobic chemical fiber
subjected to hydrophilic treatment. Examples of thermoplastic hydrophobic chemical
fibers are single fiber made of polyethylene (PE), polypropylene (PP) or polyethylene
terephthalate (PET), fiber obtained by graft polymerization of polyethylene (PE) and
polypropylene (PP), and composite fiber having core/sheath structure or the like.
[0106] Examples of the perforated plastic sheet are a perforated sheet of thermoplastic
resin such as polyethylene (PE), polypropylene (PP) or polyethylene terephthalate
(PET) and a perforated sheet of a porous foaming material.
3.1.4. Back sheet
[0107] Examples of the back sheet 14 are a thermoplastic film made principally of polyethylene
(PE), polypropylene (PP) or the like, a resin film having gas permeability, and a
composite obtained by joining a resin film having gas permeability to a nonwoven fabric
manufactured by spunbond or spunlace. A resin film is desirable, which is made principally
of a resin of polyolefin and has basis weight of 10 g/m
2 to 30 g/m
2, for example.
3.1.5. Elastic member
[0108] Examples of materials of the elastic member 91 are natural rubber and synthetic rubber
made of styrene-butadiene, butadiene, isoprene or the like. An example of the sheet-like
elastic member is a nonwoven fabric obtained from mixed fibers of a polyurethane foam
having a weight of 30 g/m
2 to 80 g/m
2, polyurethane having a weight of 20 g/m
2 to 70 g/m
2, and polypropylene.
3.1.6. Adhesive
[0109] The top sheet 11 and absorbent core 12 are adhesively joined to the chassis 13 with
the hotmelt adhesive. The top sheet 11 and the absorbent core 12 are adhesively joined
with the hotmelt adhesive. Without being limited to hotmelt adhesion, joining may
be made by heat-sealing, ultrasonic sealing, etc. alone or in combination.
[0110] An example of the hotmelt adhesive is an adhesive containing as a base polymer a
styrene-butadiene-styrene copolymer (SBS), a styrene-isobutylene-styrene copolymer
(SIS), a styrene- ethylene-butylene-styrene copolymer (SEBS), a styrene-ethylene-propylene-styrene
copolymer (SEPS), an amorphous poly-alpha-olefin (APAO) or the like. The coating patterns
when joining is made by hotmelt adhesion include spiral coating, controlled seam coating,
coater coating, curtain coater coating, summit-gun coating, etc., for example. The
weight of an adhesive for hotmelt adhesion ranges, preferably, from 1 g/m
2 to 30 g/m
2, and more preferably, from 3 g/m
2 to 10 g/m
2. With the pattern having an adhesive coated linearly, the line diameter ranges, preferably,
from 30 µm to 300 µm.
3.2. Masking sheet
3.2.1. Substrate sheet
[0111] The substrate sheets 61 and 62 can be either a liquid-permeable sheet or a liquid-impermeable
sheet. When adopting the liquid-permeable sheet, the liquid-permeable sheet illustrated
as the top sheet 11 can be used, for example. The substrate sheets 61 and 62 may be
a thin nonwoven fabric simply, such as a spunbond nonwoven fabric, pointbond nonwoven
fabric or spunlace nonwoven fabric, the basis weight of which ranges from 10 g/m
2 to 30 g/m
2. This is because a thinner nonwoven fabric provides enhanced smoothness of the band-like
portion in the stretched state.
[0112] When adopting the liquid-impermeable sheet, the liquid-impermeable sheet illustrated
as the back sheet 14 can be used, for example. The liquid-impermeable sheet may be
provided to the elastic member either on the skin contact side or on the skin non-contact
side.
3.2.2. Elastic member
[0113] Examples of the elastic members 63 are members made of natural rubber or synthetic
rubber such as styrene-butadiene, butadiene, isoprene or the like. An example of the
sheet-like elastic member is a nonwoven fabric obtained from mixed fibers of a polyurethane
foam having a basis weight of 30 g/m
2 to 80 g/m
2, polyurethane having a weight of 20 g/m
2 to 70 g/m
2, and polypropylene.
3.2.3. Adhesive
[0114] With joining of the substrate sheets 61 and 62 and the elastic members 63 or joining
of the substrate sheets 61 and 62, when joining the substrate sheets 61 and 62 with
a hotmelt adhesive, the hotmelt adhesive is coated thereon by the coating method such
as spiral coating, controlled seam coating, coater coating, curtain coater coating,
summit-gun coating or the like. The elastic members 63 are superimposed upon the hotmelt
adhesive, upon which the substrate sheets 61 and 62 are superimposed for joining.
In order to obtain hard disengagement of the elastic members 63 from the substrate
sheets 61 and 62, the hotmelt adhesive may be coated in advance by the coating method
such as slit coating, controlled seam coating or the like. Without being limited to
hotmelt adhesion, joining may be made by heat-sealing, ultrasonic sealing, etc. alone
or in combination.
[0115] An example of the hotmelt adhesive is an adhesive containing as a base polymer a
styrene-butadiene-styrene copolymer (SBS), a styrene-isobutylene-styrene copolymer
(SIS), a styrene- ethylene-butylene-styrene copolymer (SEBS), a styrene-ethylene-propylene-styrene
copolymer (SEPS), an amorphous poly-alpha-olefin (APAO) or the like. The weight of
an adhesive for hotmelt adhesion ranges, preferably, from 1 g/m
2 to 30 g/m
2, and more preferably, from 3 g/m
2 to 10 g/m
2. With the pattern having an adhesive applied linearly, the line diameter ranges,
preferably, from 30 µm to 300 µm.